RV antifreeze has been used for many years. If it was deadly leathal it would have been phazed out. You still need to give your tanks a good rinse before use. Here are a couple of souces to take a peak at.
Propylene glycol is what is found in RV Antifreeze.
After flushing out your system the trace amounts left should in my humble opinion be absolutely safe, however doing shots of it with beer chasers may not be such a good idea
http://www.peakantifreeze.com/msds/msds ... 0effect%22
"The Food and Drug Administration (FDA) has classified propylene glycol as an additive that is "generally recognized as safe" for use in food. It is used to absorb extra water and maintain moisture in certain medicines, cosmetics, or food products. It is a solvent for food colors and flavors.
Propylene glycol is also used to create artificial smoke or fog used in fire-fighting training and in theatrical productions."
"How can ethylene glycol and propylene glycol affect my health?
Eating or drinking very large amounts of ethylene glycol
can result in death, while large amounts can result in nausea, convulsions, slurred speech, disorientation, and heart and kidney problems.
Ethylene glycol affects the body's chemistry by increasing the amount of acid, resulting in metabolic problems. Similar to ethylene glycol, propylene glycol
increases the amount of acid in the body. However, larger amounts of propylene glycol are needed to cause this effect."
"Propylene glycol is generally considered to be a safe chemical, and is not routinely tested for, unless specific exposure, such as to a medicine or cosmetic, can be linked with symptoms. Since both chemicals break down very quickly in the body, they are very difficult to detect, even though symptoms may be present."
"The Food and Drug Administration (FDA) has classified propylene glycol as "generally recognized as safe," which means that it is acceptable for use in flavorings, drugs, and cosmetics, and as a direct food additive."
These are select peices of information from this site - http://www.atsdr.cdc.gov/tfacts96.html
Visit the site for more information.